Backstreet Hideout?

A couple of questions about the hideout:

Is the Backstreet hideout still obtained via the Arcade map?
If so, what is the likelihood that it shows up, because I have run around 20-30 of them and nothing has appeared yet. All of the information I can find seems to be outdated.

Yes, you can only find it in Arcade map. It is very rare. Very very rare. Having said that, I once came across it in 2 consecutive Arcades. It's pure RNG.